Proximity payment cards are in widespread use. A well known standard for such cards has been promulgated by MasterCard International Incorporated, the assignee hereof, and is referred to as “PayPass”. Proximity payment cards typically include a radio frequency identification (RFID) integrated circuit (IC) embedded in a card-shaped plastic body. An antenna is also embedded in the card body. The antenna allows the card to receive a power signal from a point of sale terminal. The antenna is also used by the RFID IC to transmit the payment card account number, and possibly other information as well, to the POS terminal.